Insulating a pole barn

Pole barns were designed to let farm animals get under shelter, most farmers don’t insulate the walls. Insulation for them is usually either inadequate to make the space livable for humans, or costs so much you can’t afford it.

I don’t know what to tell you except checking to see what spray foam insulation’s cost would be for the walls. I built a 32×48 a few years ago, and was thinking pole barn all the way, like you thinking economical…..

I ended up with a 32×48 x 12 garage built building on a full concrete slab for 3 grand less than the cheapest pole barn, with no floor, and options to insulate costing me thousands more than regular batt insulation in my walls, and blown in insulation up top. I have r 23 walls, and r 48 roof. Cozy digs.

I don’t want to appear like a smarty here, but do not just look at price to put “something” up. Look at a price to attain a certain R value, cause you can spend a fortune on that roll out batting 6’ wide x 50’ long, and end up with an R of less that 5. There is absolutely no level of common sense to that at all. Especially when you consider you would need several rolls just for one layer. After a first layer your options with them are to add additional framing…....

You won’t like this, but I’d suggest doing the math to see what lumber costs would be to completely line the area within your pole structure you want to insulate, so if you want the entire thing insulated find out how much for lumber to frame walls inside your pole structure, then insulate conventionally with much lower priced options. Options you can install yourself. You will find the dead space between the sheating of the barn (provided it is tight, and not open to allow air/wind full access,) is going to increase your R yield immensely.

Another option is to do nothing, buy a 220 k salamander heater and let her rip, turn it off when you start getting hot, and back and forth.

-- Think safe, be safe

I just finished my building. I have a 30X30 “pole building” with corrugated steel roof and external walls. Like you describe, it was just a shell. I used R-38 bats for the ceiling insulation and I got white corrugated metal to hang up as the ceiling itself. For the insulation and interior walls I used the same thing, white corrugated metal and I mounted it on 2X4 purlins nailed on horizontally on 2 ft centers.
I had enough space between the exterior metal and the purlins to run insulation vertically. I don’t remember the R number but I want to say R-22 or 23 rings a bell. You order the metal cut to the length you need. It is all 3 foot wide. For the ceiling I used 16 foot length metal and let it overlap in the middle. The interior walls need to be measured carefully, not much room for error.
I installed a wood stove for heat and a 220v window unit for AC. This building heats up and cools down fast. All that said, I don’t live in Maine and I don’t live in Florida either. I was putting the R-38 bats in the ceiling from a ladder as I hung it so I didn’t have to go up there crawling around on the roof trusses. There is a C-channel that goes on the top of the side wall metal to give it a nice finished look. I did use rigid foam panels to insulate the sliding doors. I covered the inside of the doors with 1/4” plywood and painted it gloss bright white. This really made a very nice workshop that looks good and holds the heat and cool air. I am a pretty good drywall finisher, but this was fast to do compared to hanging drywall and finishing and painting it. One other good thing is that dust doesn’t stick to the vertical smooth metal or the ceiling…what really fine stuff that does blows right off with an air hose.

Edit: I should add that I have square 6X6 “poles”...if you have round poles in yours you can run the purlins between them and toe nail level with the pole instead of on the face of the pole. This will reduce the space you need to insulate.

Another thing on a “metal roofed” open building is to check locally with folks who USE them, and find out about rainfall. In SW Ohio it’s not uncommon for uninsulated buildings to actually rain inside when humidity goes way up, and there is a lot of ground moisture. I have been given to understanding in other parts of the country the problem is only after insulating, but same thing, moisture in the building saturates the batt type insulation making it pretty useless. There I think a vapor barrier would fix things. Up here a vapor barrier and insulation will stop the rain.

In either case if they are left open, so air can circulate freely it goes away, it’s only when you put in valuables, and keep them locked/closed up you have the problem.

-- Think safe, be safe

Moisture/humidity can be a problem. I have built two buildings, one a cabin on top of a mountain and the other my workshop, that both have metal roofs with exposed metal on the interior. That is to say, I can go up in the attics of either and touch the metal roofing. Many buildings with metal roofs have the roof sheathed with plywood first and have a “barrier” between the metal and the plywood sheathing.
So far, I have not had any water problems with either. I just did the workshop over this past winter and I built my cabin in 2011. Both have a full length ridge vent and both also have vented soffit. The cabin has gable vents too, which I may put on the workshop. You cannot have too much ventilation when it comes to attic or crawl space.
I did have some high humidity in the workshop. During the winter, when I was building it there was none and once I got the woodstove operational there really was none, but as soon as it started to warm up I had rust on my machine tables. Paste wax cured that, but the moisture was still high. I don’t run the AC all the time, only when I am there working. I had to install a dehumidifier and that easily keeps it at 50% humidity.
Interesting enough, I have never had a humidity problem at the cabin…the difference? Cabin is built on a crawl space, workshop is on a slab. Cabin stays closed up tight most of the time {bears}. Both are in the mid-Atlantic region and we suffer periods of high humidity. Bottom line, I have been watching, but so far no trouble.

Jim if you check a local lumberyard i’m sure they can help you out. For pole barns they sell large bats that you fasten at the top and let roll down in between your posts, very slick and easy. Obviously spray foam is a great option also, but more expensive. Around here pole barns are insulated all the time with no issues, many would argue they are insulated better due to not having studs every 16”.

heres a link of one example

https://www.silvercote.com/products/faced-blanket/

-- if it is to be it is up to me

Thanks for the helpful options.
One of the factors causing cost to go up is the off size of the addition. 14×22 not exactly standard but didn’t have much choice.
No matter what insulation I use it seems I will have to put up osb on the walls.
I will have to check out those large roll out bats.
I’ve built my own pole barns for my cattle and machinery but a workshop brings a whole new meaning to the cost factor :)

New workshop, lucky you!

+1 msinc and therealStevenN statements:
Hard part of a pole structure is controlling moisture inside .vs. outside, especially when you do not have HVAC running 100% of time. Need to carefully consider moisture control to protect tools. Using roll insulation or spray foam as part of vapor barrier helps a lot (not to mention noise reduction).

Suggest that if your concrete floor does not have a plastic moisture barrier underneath, that you must epoxy seal the concrete (after is fully cured and ground is relatively dry). Concrete floor without moisture barrier is losing battle when trying to control humidity and stop rusting on cast iron tools. Even if it does have vapor barrier, sealing concrete with simple clear sealer will help reduce moisture ‘storage’ in floor when you are not controlling the temp/humidity. Sealing concrete will also improve dust control. Concrete has opens pores that allows dust to hide inside. Sealed floor makes is much easier to prevent dust issues in shop for flawless spray finishing.

Best Luck.

-- I'm an engineer not a woodworker, but I can randomly find useful tools and furniture inside a pile of lumber!

Goofy video, but I have heard this is pretty good. I am starting to build and looking into this.

https://www.youtube.com/watch?v=fB5CH-834gk

-- Dave

Yes There is 6mil under the slab. I wanted to put ridged foam under also but the mason didn’t think it would matter especially with 5”of stone and 5” of fiberglass concrete. Yes I plan on sealing the floor.
For the curious: the object you see looking out the garage door (6’ wide 8’ high) is the barn. As far as epoxy on the floor, wait time is at least 90 days and central PA has had nothing but rain, rain, rain. If I seal it now I will have to strip the sealer and hope I get it right. I hate to wait till next summer for putting down epoxy. Probably better to just bring in the machinery, be careful of oil and just do half at a time next summer.
Thanks,
Jim

I am framing out the inside walls to 6” so I get a nice flat interior wall. I was about to put 6” paper faced insulation in the walls. Paper facing on the inside. I got to worrying about the insulation picking up condensation from the metal panels especially if it contacts the metal. And because its out of sight you probably never know it is happening.
I have thought of two possible cures. Staple 6mil plastic to 2×4 purlins and lap it to the 6×6 uprights. Or do the same with foil faced double bubble, maybe even faced both sides. But that bubble stuff is costly.
If anyone has some first hand experience I would appreciate hearing it.